The tapes start out going right into immediate exercises, which I'm not used to. Even Tae Bo has you warm up first. But, maybe the exercises she starts with are part of a warm up. All I know is as soon as it starts she wants your heart rate to skyrocket. The "front" workout has you start with a high kick where your feet kick forward and to the side (as high as your waist, she insists - hah!) as a first move; I believe 30 times, alternating legs. The "back" workout has you start with some combination of jogging in place combined with knee lifts. It does indeed make your heart skyrocket, and personally I can't even do 30 of each as she does. But I AM a beginner.
The tapes require just two things, an aerobic step and some light hand weights. (I use 3 lb dumbells). She goes through some circuits that include many of the exercises from her book. Each circuit is repeated before moving on to the next one. She does a good job at mixing large-muscle exercises simultaneous with small-muscle exercises, so it keeps your heart rate going. Personally I look forward to the part of the circuit that requires you to lay on the floor.
I think the whole workout is about 30 mins, and includes such exercises as crossover lunges, dead-man lifts, mountain climbers (everyone's favorite), buttkicks while doing hammer curls, and jumping jacks while lifting the weights over your head. She ends with some cool-down stretches.
I think 30 mins of cardio on a treadmill would be a good thing to do before starting the DVD workout. That way you're getting your 1 hour in. Its nice that the front workout is separate from the back, so every other day those muscles get a rest.
Jillian yells at "you" a few times during the workout ('don't even THINK of stopping now!'), and likes to be evil to the people doing the workout with her. If I'm alone, I yell some pleasant words back at her.
It's a tough, grueling 30 mins, but it is a great intense workout if you can keep with it!